Antimicrobial and Cytotoxic Activities of Colloidal Silver and Titanium Dioxide Nanoparticles Against Food-Borne Bacteria: Shigella dysenteriae and Staphylococcus aureus

Nowadays, due to the increasing problems of microbial resistance, scientists are searching for the safest and most effective way to fight them. The colloidal silver (Ag) and titanium dioxide (TiO2) nanoparticles can effectively fight against many bacterial microorganisms. Therefore, the purpose of this study was to investigate the antibacterial and cytotoxic properties of Ag and TiO2 nanoparticles, against Shigella dysenteriae and Staphylococcus aureus.

In this study, Ag and TiO2 nanoparticles were synthesized, and the minimum inhibitory and bactericidal concentrations (MIC & MBC) were determined. In addition, the cytotoxicity of these agents was evaluated on Hu02 fibroblast cell line.

We found that the MIC and MBC for Ag and TiO2 nanoparticles were similar (12.5 µg/ml) against S. aureus, while the MIC’s for Ag and TiO2 against S. dysenteriae were found to be 12.5 and 25 µg/ml. In addition, the MBC’s for Ag and TiO2 against S. dysenteriae were 25 and 50 µg/ml. Based on the cytotoxicity tests, the cell viability percentage after 48 hours of exposure to TiO2 was higher than that of Ag (0.025 µg/ml).

The Ag and TiO2 nanoparticles demonstrated good antibacterial properties while they had low toxicity against the Hu02 fibroblast cell line.